研究分析了腐殖酸对水溶液中纳米TiO2稳定性的影响，探究了混凝剂投加量、pH、钙离子对混凝-超滤工艺去除水中腐殖酸-纳米TiO2复合污染物的影响。结果表明，纳米TiO2与腐殖酸在水溶液中发生的静电吸附以及配位反应将引起纳米TiO2有效粒径的减小，静电斥力增强，胶体分散更均匀，体系稳定性增加，易于迁移，从而给饮用水安全带来威胁。实验结果显示，混凝剂浓度为0.46 mmol/L，pH值在7~8之间，即弱碱性时，不添加钙离子，处理效果较好，膜通量较高，膜污染较轻。

The effect of humic acid (HA) on the stability of nano-TiO2 was analyzed, and the effects of coagulant dosage, pH and calcium(Ⅱ) concentration on the removal efficiency of HA- TiO2 composite pollutants by the coagulation-ultrafiltration process were investigated. The results showed that the electrostatic adsorption and coordination reaction occurred between nano-TiO2 and HA in the aqueous solution, which caused the decrease of effective particle size of nano-TiO2, the enhancement of electrostatic repulsion, more uniform dispersion of colloid, the increase of system stability and easy migration. These posed a threat to the safety of drinking water. The optimum parameter for HA-TiO2 composite pollutants removal was that the coagulant concentration is 0.46 mmol/L, and the initial pH value is between 7 and 8. The calcium ion in the solution will lead to the decrease of membrane filtration flux and increase the membrane fouling.

国家自然科学基金项目（面上项目，重点项目，重大项目）